Yeah any bolt on basically you want to reset ECU because you put on a different aftermarket part that your ECU of the car was configured for the stock parts. So you would want to either remove fuse #15 under the Hood or just detach the black battery terminal while installing your exhaust. So when you turn on your car with the mod installed the ECU will re-configure itself for the new mod and your set to go!

Yeah any bolt on basically you want to reset ECU because you put on a different aftermarket part that your ECU of the car was configured for the stock parts. So you would want to either remove fuse #15 under the Hood or just detach the black battery terminal while installing your exhaust. So when you turn on your car with the mod installed the ECU will re-configure itself for the new mod and your set to go!

It doesn't matter if your CEL comes on or not, if you put a new mod on your car, then you should reset the ECU. People who don't reset there ECU right away sometimes don't feel the major difference of the mod. The ECU will re-learn and adjust for the new mod, but it can take up to 2-weeks of driving. So do yourself a favor and reset the ECU.

i just recently installed an HKS hi-power exhaust on my 03 celi...i never did reset my ECU, just wanted to know that without resetting the ECU it should eventually reset itself and I should be good, right? Its been a couple of months now...should i still go ahead and reset it just to be on the safe side?

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